Electrically operated printer



Oct. 12, 1965 J. G. BOLGER, JR 3,211,371

ELECTRICALLY OPERATED PRINTER Filed D60. 31, 1962 INVENTOR JOHN G. BOLGER JR.

w/fda nw ATTORNEYS United States Patent 3,211,371 ELECTRICALLY GPERATED PRINTER John G. Bolger, .lr., Lafayette, Calif, assignor, by mesne assignments, to Bank of California NT & SA Filed Dec. 31, 1962, Ser. No. 248,306 14 Claims. (Cl. 235-58) This invention relates to an electrically operated printer which automatically selects the desired data to be printed by a group of printing wheels, and immediately thereafter stamps the raised characters on these wheels against a printing surface, thereby causing them to print the data.

Various highly complex electrically operated printers, normally associated with electronic computers, are well known in the art. There is still need, however, for a very simple inexpensive printer to handle a relatively small number of printed characters. For example, such a printer might be used to print ticker tape information in stock brokers ofiices where they are received as electronic symbols from New York. Inventory information and counts might be printed in warehouses anywhere in the country from a central computer; or game scores could be printed directly from an electronic tally. The following detailed description of the invention uses bowling score tabulation as an example. This provides a very good illustration of one use of the invention. However, it should be borne in mind while reading this specification that bowling score tabulation is just one of the many possible uses of the electrically operated printer of this invention.

In the past, bowling scores have been tabulated manually by skilled and highly paid scorekeepers. They record line and frame scores, perform the required arithmetic, and project the results on a screen for spectator viewing. Because of the large labor cost and many human errors associated with this system, automated scorekeeping systems are now being developed. For example, equipment is available for electronically sensing and recording the pins falling as a result of each ball bowled. This equipment is described in copending application Serial No. 178,873, filed March 12, 1962, now Patent No. 3,140,872 of the same inventor and assigned to the same assignee as this invention. The output of such a pin-sensing appa ratus is fed to a specially designed electronic computer where the data is tallied. This tallied data is finally printed in a form which may be projected for viewing. Bowling scores are always expressed in the form of a number from 0 to 300, or by the symbol X for a strike or the symbol for a spare. There is need for a simple apparatus that can electrically set up the cumulative score (and the spare and strike symbols) for printing, and thereafter automatically cause it to be printed for subsequent projection. Since there are in operation in the United States alone about 200,000 bowling alleys which could use such an electrically operated printer, it must lend itself to mass production.

This invention provides an electrically operated printer which fulfills all of the above requirements. Briefly, the electrically operated printer of this invention, in response to one or a series of electric signals, places a desired set of characters in printing position. Then, in response to another (single) electric signal, the apparatus prints the desired characters on a suitable surface. These characters may be numbers, letters, symbols, or the like, and are located around the circumference of rotatable printing wheels. They are raised in order that they may print directly on the printing surface after the proper amount of rotation of the wheels has placed the desired characters in printing position. For bowling scores, three numerical Wheels are required in addition to the strike and spare symbols. The strike and spare symbols are preferably raised somewhat more than the numerals, to prevent a ice cumulative score from printing when a strike or spare symbol is printed.

The three printing wheels used to print the cumulative score (herein called the score wheels) each have ten digits embossed around their circumference. They are connected with a rotator, such as a solenoid mechanically linked to gears on each wheel, in such a manner that each time the solenoid is energized the count on the score wheels is increased by one. The electric signal used to energize this solenoid is an electric pulse, or a chain of such pulses. Each pulse will increase the count (the cumulative score to be printed by the score wheels) by one. If, for example, a ten-pulse electric signal is sent to the rotator, the total indicated by the numerals on the score wheels will be increased by ten.

The fourth wheel on the electronic printers of this invention, when used for bowling scores, has only two characters; one is the spare symbol and one is the strike symbol. One electric signal places the spare symbol in printing position, another the strike symbol. The details of these actions will be more fully understood from the following more specific description and reference to the drawings, in which:

FIG. 1 is a side elevation view, partially broken away in section, showing an electrically operated printer of this invention, including the printing surface and its support;

FIG. 2 is a sectional rear view of the printing element taken in the plane 2-2 of FIG. 1;

FIG. 3 is a sectional plan view taken in the plane 33 of FIG. 1, showing a score wheel, the spare-strike wheel, the printing surface, the resilient support for the printing surface, and the rotator for the spare-strike wheel;

FIG. 4 is a fragmentary cross-sectional view of the spare strike wheel in the strike-printing position;

FIG. 5 is a fragmentary cross-sectional View of the spare-strike wheel in the spare-printin g position;

FIG. 6 is a bottom view looking up at the spare-strike wheel, and showing the spare and strike symbols; and

FIG. 7 is a sectional elevation showing the rotator for the spare-strike wheel, taken in the plane 77 of FIG. 3.

In a number of instances duplicate parts are shown on more than one figure of the drawings. Parts that are best displayed in FIG. 1 are given numbers 1-19; parts best displayed in FIG. 2 are given numbers 20-29; parts best displayed in FIG. 3 are numbered 30-39; and so forth. Where these parts are also shown in other figures, their original numbers are used.

Referring to FIG. 1, the printing element is rotatably mounted on support 2 by shaft 32. The raised characters to be printed are disposed on printing wheels, of which one (the spare-strike wheel 3) is shown. A solenoid 4 is contained in shell 5, and is used to cause printing element 1 to print. When an electric printing signal is received by solenoid 4, shaft 6, which is pivotally connected to printing element 1 at pivot 7, is pulled toward solenoid 4 by the action of the solenoid. This motion causes printing element 1 to pivot on shaft 32, extending spring 8, so that the selected printing wheels strike printing surface 9. In the position in which the spare-strike wheel 3 is shown in FIG. 1, called neutral, neither the raised strike symbol 61 nor the raised spare symbol 62 can print; only a numerical (cumulative) score will print. This will be more fully explained later. When a spare or a strike is scored, spare-striking printing wheel 3 is moved into printing position by pulley 10 connected to the spare-strike wheel 3 by belt 11. Shell 5 is pivoted at point 12 to prevent its hindering the printing motion of element 1.

After completion of the printing, shaft 6 is released from solenoid 4 and printing element 1 is returned to the neutral position by loaded spring 8. If the next impression is to be made in a diiferent location, printing surface 9 is moved so that the desired portion of the surface is located beneath the printing element. The details of the mechanism used for moving the printing surface, as well as a full description of the two-layer printing surface 9 having an upper layer of paper and a lower layer of carbon-coated plastic, may be found in copending application Serial Number 248,805, filed concurrently herewith. Preferably, the support 13 beneath printing surface 9 is slightly resilient to absorb the shock as printing element 1 strikes the printing surface.

The counting portion of printing element 1 may be best understood by reference to FIG. 2. Three score wheels 20, 21, and 22 are used to represent the hundred-s digit, the tens digit, and the units digit, respectively, of the cumulative score. In this view it may be seen that when the spare-strike wheel 3 is in the neutral position illus trated, the raised numerals on score wheels 20, 21, and 22 extend radially beyond the spare and strike symbols in the lowermost, or printing position. In this position, the score wheels, but not the spare-strike wheel, will strike the printing surface during the printing motion and so print.

The score Wheels 20, 21, and 22 are rotated in such a manner that the cumulative score is always disposed lowermost (i.e., in printing position). This score is represented by the units digit disposed on wheel 22, the tens digit on wheel 21, and the hundreds digit on wheel 20. To increase the cumulative score by a count of one, pinion gear 24, which is linked to pinion gear 27 (which in turn is linked to wheel 22) is rotated one position by a mechanical linkage to solenoid 23. Such a linkage is Well known in the art. Solenoid 23 is energized to cause this rotation by an electric signal. Each successive electric signal causes pinion gears 24 and 27 and units wheel 22 to rotate one position, increasing the number disposed lowermost on units wheel 22 by a count of one. Whenever this lowermost units number changes from nine to zero, ten wheel 21 is rotated one position by pinion gear 26 so that the number disposed lowermost on it is increased by a count of one; and in turn, when tens wheel 21 changes from nine to zero, pinion gear 25 causes hundreds wheel 20 to increase the number disposed lowermost on it by a count of one.

The pulses to solenoid 23 need not be single pulses; a chain of pulses may be used to increase the cumulative score indicated by the numbers disposed lowermost on score wheels 22, 21, and 20 by the number of pulses in the chain. For example, if the score wheels indicate a value of one hundred twenty-one (121), and a count of nine (9) is to be added, the signal to solenoid 23 would be a chain of nine pulses, and would energize the solenoid,

nine separate times. This rotates units wheel 22 nine places, from one to zero; as the zero moves into printing position on units wheel 22, tens wheel 21 rotates one place, from two to three. The hundreds wheel 20 would not rotate, because the tens wheel 21 did not pass from nine to zero. Thus, the new cumulative score of one hundred thirty (130) will be set for printing. A signal to printing solenoid 4 then causes the printing operation, as explained above.

As the bowling continues, the scores are added continually to the cumulative score shown by the counter in the manner described above, until the game is finished. When a spare or a strike is bowled, the procedure is varied slightly, because one or two of the next balls are counted twice in scoring; the frame score is therefore not completed until these later balls have been bowled. Instead of an immediate score, then, the symbol (for a spare) or X (for a strike) is printed. These symbols are located on spare-strike printing wheel 3. Whenever these symbols are printed, score wheels 20, 21 and 22 cannot print (for reasons described later). In the case of a strike,

the frame is completed as soon as two more balls have been bowled; for a spare, onemore ball is necessary. After these balls have been bowled, the score for the frame is finally printed, next to the spare or strike symbol.

A very important feature of the invention is the method by which the printing force is applied. To obtain a clear, undistorted impression of the raised characters, a fairly heavy striking force is required. With conventional printers, compromise has always been necessary between the desired striking force and the danger of damage to the shaft containing the printing wheels. Where this shaft is pivotably mounted in the sides of the printing element, all the striking force is transmitted to the ends of the shaft, and it has not been uncommon for it to bend, eventually, under the heavy continual force.

In FIG. 2A, it may be seen that shaft 28- is slidably mounted in slot 29. The shaft is normally held in the lowermost position in slot 29 by springs 28a. When the printing operation begins, printing element 1 is moved downwardly against the printing surface. When one of the printing wheels (such as counting wheel 22, shown in FIG. 2A) strikes the printing surface, shaft 28 is caused to slide upwardly in slot 29. This sliding motion is stopped by backing bar 40, shown in both FIG. 2 and FIG. 2A. This backing bar is rigidly fastened, as by casting, to the sides of printing element 1 (as shown in FIG. 2). The numeral (on wheel 22) which lies diametrically opposite from the one about to be printed will strike against backing bar 40. Thus, the striking force, instead of being transmitted through the ends of shaft 28 as was the case with prior printing elements, is transmitted diametrally through the printing wheels themselves. When the element is not printing, springs 28a hold the wheels away from backing bar 40 to allow them free rotation during the counting or scoring process.

In prior printing elements, this large force exerted on the ends of shaft 28 required that the shaft have considably greater diameter than the shaft used in this invention. In addition, bearings were frequently needed in the mounting. These features increased the driving power required to rotate the score wheels while decreasing the speed of their rotation. The shaft of this invention, not being subject to such heavy force, can be made long enough to accommodate a large number of wheels without any danger of its buckling under the printing stress. Diametral transmission of force through the wheels has been found to provide a very clear printed image of the desired character. Further description will be found below in connection with the spare-strike wheel.

The operation of spare-strike wheel 3 may best be seen from FIGS. 3, 4, and 5. In FIGS. 4 and 5, the sparestrike wheel 3 is shown in position ready to print one of its two symbols. When wheel 3 is in either of its printing positions, the strike symbol and the spare symbol extend radially beyond the raised numerals of score Wheels 20, 21, and 22. In FIG. 4, the strike symbol 61 is shown in contact with printing surface 9. Its greater radial extension prevents score wheels 20, 21, and 22 from coming in contact with printing surface 9. In FIG. 5, the spare symbol 62 is shown in contact with printing surface 9; its greater radial extension has the same effect.

Referring now to FIG. 3, spare-strike wheel 3 is rotated from neutral position to the spare or strike position by the action of solenoids 70 and 71. When solenoid 71 is energized, shaft 32 and pulley 10 are rotated counterclockwise. Pulley 10 is connected to pulley 60 on sparestrike wheel 3 by belt 11. As shown in FIGS. 4 and 5, belt 11 is prevented from moving, relative to pulley 60, by a knife-like extension 46 on pulley 6d. Belt 11 may be a spring, as illustrated, or other conventional elastic belt. Knife-like extension 46 is wedged between the coils of the spring and holds it securely to pulley 60. The counterclockwise rotation of pulley 10 thus causes a similar counterclockwise rotation of pulley 6t), bringing the spare symbol 62 into printing position. I

Conversely, when solenoid 71 is signaled, shaft 32 and pulley are rotated clockwise, bringing strike symbol 61 into printing position. The rotation of shaft 32 and pulley 19 is again transmitted to spare-strike wheel 3 by belt 11. The signal to one or the other of these solenoids is maintained during printing; then it is stopped and the energized solenoid 70 or 71 is held in its neutral position by leaf spring 33.

Summarizing with reference to FIGS. 4, 5, 6, and 7, a spare signal to solenoid 70 rotates pulley 6!!) counterclockwise, as shown in FIG. 5. Spare symbol 62 is then in printing position. A strike symbol to solenoid 71, on the other hand, rotates pulley 60 clockwise, as shown in FIG. 4. Strike symbol 61 is then in printing position. After the desired symbol has been printed, the energized solenoid 70 or 71 is released, allowing extended leaf spring 33 to return to its normal position, thereby holding spare-Strike wheel 3 in the neutral position shown in FIG. 6. Because of the force with which the spare-strike wheel 3 strikes the printing surface 9, it is advantageous for production of a clear image that this force be transmitted through a diameter of printing wheel 3; this also minimizes strain on the wheel. For this purpose, printing wheel 3 has raised portions 51 and 52 located diametrically opposite from the strike and spare symbols 61 and 62, respectively. The printing force is then transmitted from abutment 40 through a diameter of printing wheel 3 extending from raised portion 51 or 52 to symbol 61 or 62, respecttively (depending upon whether a strike or a spare is to be printed). This diametral transmission of force produces a very clear and distinct image of the spare and strike symbols on the printing surface 9.

Stops 43 and 44 are used to locate the spare and strike symbols for precise printing. A strike is printed when stop 43 of printing wheel 3 hits against abutment 40 (shown in FIG. 4); a spare is printed when stop 44 of printing wheel 3 hits against abutment 55.

At the close of the game, after the final score has been printed through the action of printing element 1, score wheels 20, 21, and 22 must be reset to zero for the next game. This is accomplished by a conventional ire-setting mechanism contained in the counting portion of printing element 1 shown in FIG. 2. Such mechanisms are well known in the art, and therefore no further description is believed necessary here. Re-setting may be accomplished manually, or by an electric signal, as desired.

Summarizing now the operation of the entire electrically operated printer, consider the situation wherein there is a previous cumulative score of two (2); the player now knocks down a total of one pin on the next frame (having bowled both his balls). His new score, as a result of this frame giving him one additional point, is three (3). An electric signal is automatically transmitted from the pin-sensing apapratus to a computer, which in turn sends a one-pulse electric signal to solenoid 23. This signal moves units wheel 22 (which was previously set at two) one place, thus setting it to three. This action takes place virtually instantaneously. Immediately thereafter, the computer sends a second electric signal to solenoid 4 which causes printing element 1 (with the spare-strike wheel 3 in neutral position) to print the number 3 which has been set in the score wheels. The printing surface 9 is then automatically advanced to the next position.

Now suppose that on the next two balls the player bowls a spare (all ten pins knocked down after the second ball). A continuous pulse is sent to solenoid 70, placing spare symbol 62 in printing position; immediately thereafter, an electric signal is sent to solenoid 4 and the spare symbol 62 is printed. The pulse to solenoid 70 then ceases and spare-strike wheel 3 is returned to the neutral position by the action of leaf spring 33. Printing solenoid 4 is returned to the non-printing position by the action of spring 8; this time, however, the printing surface 9 is not advanced, because a spare permits the bowler 5 one additional score (the next ball is counted twice, once for this spare frame and once for its own frame).

Suppose further that the next ball bowled (in the following frame from the spare frame) resulted in a knockdown of seven more pins. The additional seven points are now added to the ten points added for the spare, giving a total score increment of seventeen (17) points for the spare frame. The computer then sends a seventeen-pulse signal to counting solenoid 23, thereby increasing the amount shown on the score wheels from three to twenty. Solenoid 4 then receives a print signal, and causes the score 20 to print, adjacent to the symbol in the spare frame, as shown in FIG. 3. Printing surface 9 then advances one frame.

The second ball in the current frame is now bowled (the first ball having knocked down seven pins, as discussed above), and knocks down two more pins. The computer adds these two points to the seven points for the first ball and arrives at a total score of nine for this frame. A nine-pulse signal is then sent to the counter, increasing its setting to twenty-nine. A print signal to solenoid 4 now follows, and the cumulative score 29" is printed in the new frame. Printing element 1 is now returned to the non-printing position by spring 8, and printing surface 9 is advanced, ready for the next frame.

Note that the score of seven for the first ball in the frame immediately following the spare frame was added twice. In bowling scores, one extra score is earned by a spare; however, instead of bowling an extra ball to determine this score, the first ball of the following frame is counted. For this reason, the first ball of the following frame (the one following the spare frame) is counted twice-once for the spare bonus and a second time for the frame in which it was actually bowled. Similarly, a strike earns two extra scores, so that both balls in the following frame count twice, once for the strike bonus and once again for the frame in which they are bowled. Should the first bonus ball be a strike, also, the first ball of the next succeeding frame would be counted for the bonus points on the first strike.

As explained earlier, the invention is not limited to bowling. For use in ticker-tape information, three printing wheels would carry letters, another three would carry digits, and another would carry fractions. A second group of wheels might carry the number of sales. The operation of the apparatus, however, would be identical to the operation described for bowling, with suitable modifications obvious to one skilled in the art. Because of the many modifications .and adaptations possible for the invention, the only limitations to be placed upon its scope are those expressed in the following claims.

What is claimed is:

I. An electrically operated printer which automatically disposes in a printing position in response to a first electric signal a desired set of characters to be printed, and thereafter causes said characters to strike on a printing surface in response to a second electric signal, which comprises:

a plurality of rotatable printing wheels, each having a plurality of raised characters spaced around its circumference, said wheels being rotatable so that any one of said characters may be disposed in said printing position, one of said wheels having its characters raised further than those of another of said wheels, so that when a character of said one of said wheels is disposed in said printing position, the characters of said other of said wheels are prevented from printing;

a comm-on axis supporting said wheels coaxially so that said further raised characters extend further in a radial direction from said axis than the remaining characters;

support means supporting said common axis, said support means being hinged so as to be capable of being swung in and out of printing position;

rotating means for each of said wheels adapted to rotate them on said axis so as to place selected char- 7 acters in printing position, said rotating means operating in response to said first electric signal; and means for striking said support means against a printing surface in response to a second electric signal, thereby causing the characters so disposed on said wheels to be printed thereupon.

2. The electrically operated printer of claim 1 further defined by at least some of said wheels comprising a counter, each wheel of which having the raised numerals through 9, said counter adapted to increase the numerical value of the number to be printed in response to said first electric signal.

3. The electrically'operated printer of claim 2 further defined by said rotating means including a first solenoid mechanically linked to one of said counting wheels so that the action of said solenoid, when first energized once, increases the said numerical value of said number to be printed by one.

4. An electrically operated printer which automatically disposes in a printing position in response to a first electric signal a desired set of characters to be printed, and thereafter causes said characters to strike on a printing surface in response to a second electric signal, which comprises:

a plurality of rotatable printing wheels, each having a plurality of raised characters spaced around its circumference, said wheels being rotatable on a shaft so that any one of said characters may be disposed in said printing position;

means for slidably holding said shaft to allow said shaft to slide between two alternate positions, the first of said positions being one in which said wheels are free to rotate so that any one of said characters may be disposed in said printing position, and the second of said positions being one in which the character on each such Wheel located diametrically opposite the character disposed in said printing position is forced against a rigid member during printing, thereby applying a force from said rigid member through the diameter of each of said wheels and through the characters disposed in said printing position, to cause said characters to print;

rotating means for each of said wheels causing same to rotate when said shaft is in said first position in re sponse to said first electric signal; and

means for striking the characters disposed in said printing position against a printing surface in response to said second electric signal, thereby forcing said wheels against said rigid member and causing the characters disposed in said printing position to print.

5. The electrically operated printer of claim 4 wherein said striking means applies a force for printing each of said two characters against said wheel at a point on its circumference diametrically opposite from the location of said character.

6. The electrically operated printer of claim 5 wherein said wheel has a raised portion adjacent to the point of contact between said striking means and the circumference of said wheel when either of said characters is disposed in printing position.

7. An electrically operated printer which in response to a first electric signal automatically disposes in printing position a desired character to be printed and thereafter causes said character to print on a printing surface in response to a second electric signal, which comprises:

a rotable printing wheel having two raised characters spaced around its circumference, either of Which may be disposed in printing position by rotation of said wheel;

rotating means for said wheel which operates in response to said first electric signal which is one of two signals, one of which causes one of said characters to be disposed in printing position and the other of which causes the other of said characters to be disposed in printing position, said means including:

(a) a first pulley attached to said wheel so that rotation of said pulley causes a like rotation of said wheel;

(b) a second pulley;

(0) means connecting said first pulley to said second pulley whereby rotation of said second pulley causes a like rotation of said first pulley, and therefore of said wheel; and

(d) means for rotating said second pulley in either direction, rotation in one direction causing one of said two characters to be disposed in printing position and rotation in the other direction causing the other of said two characters to be disposed in printing position.

8. The electrically operated printer of claim 7 wherein said rotating means for said second pulley includes:

(a) two solenoids, one of which is energized by one of two said electric signals and the other of which is energized by the other of said two electric signals, one of said solenoids being mechanically linked to said second pulley so as to cause it to rotate in one direction and the other of said solenoids being mechanically linked to said second pulley to cause it to rotate in the other direction; and

(b) means for returning said second pulley and therefore said first pulley and said wheel to a neutral position wherein neither of said characters is printed in response to said second electric signal alone.

9. The electrically operated printer of claim 8 wherein said returning means includes a leaf spring mounted rigidly at one end and having the free end in contact with the shafts of both solenoids, whereby said shafts are held in the neutral position by said leaf spring except when one of said solenoids is energized.

10. An electrically operated printer which in response to a first electric signal automatically disposes in a printing position a desired set of characters to be printed and thereafter causes said characters to print on a printing surface in response to a second electric signal, which comprises:

a plurality of rotatable printing wheels rotatably mounted on a support, each wheel having a plurality of raised characters spaced around its circumference, any one of which may be disposed in said printing position;

rotating means for rotating said plurality of printing wheels to dispose a desired set of characters in printing position, said rotating means actuated by said first electric signal;

a single rotatable printing wheel having two raised characters, said characters extending radially from said wheel a greater amount than the characters on said plurality of rotatable printing wheels, whereby when one of said two raised characters is disposed in printing position, the raised characters on said plurality of wheels are prevented from contacting the printing surface;

rotating means for rotating said single rotatable printing wheel among three positions, one of said positions having one of said two raised characters disposed in printing position, another of said positions having the other of said two raised characters disposed in printing position, said third position being one in which the contents of said plurality of printing wheels may print; and

means for automatically causing said printer to print in response to a second electric signal.

11. An electrically operated printer which automatically disposes in a printing position in response to a first electric signal a desired set of characters to be printed and thereafter causes said characters to print on a printing surface in response to a second electric signal, which comprises:

a plurality of rotatable printing wheels rotatably mounted on a support, each having the numerals zero through nine spaced around the circumference thereof, each of said wheels being rotatable so that any one numeral on each Wheel may be disposed in said printing position, said wheels forming a counter adapted to increase the numerical value of the number disposed in said printing position in response to said first electric signal;

a single rotatable printing wheel rotatably mounted on said support, said Wheel having two raised characters spaced around its circumference and being rotatable so that either of said two characters may be disposed in said printing position in response to said first electric signal;

means for rotating said plurality of wheels, said means including a first solenoid mechanically linked to said plurality of wheels so that said wheels are rotated to increases the numerical value of the number disposed in said printing position by one each time said first solenoid is energized, said solenoid being repeatedly energizable by said first electric signal;

means for rotating said single rotatable printing wheel in response to said first electric signal which is one of two electric signals, one of which causes one of said two characters to be disposed in printing position, and the other of which causes the other of said two characters to be disposed in printing position;

holding means for pivotably holding said support away from contact with said printing surface;

means for pivoting said support on said holding means so that said disposed characters strike said printing surface, said means including a second solenoid which is energized by said second electric signal; and

means for restoring said support to its position away from contact with said printing surface.

12. The electrically operated printer of claim 11 wherein one of said two characters is a spare symbol and the other is a strike symbol.

13. The electrically operated printer of claim 12 where said means for rotating said single rotatable printing wheel includes two solenoids mechanically linked to said single wheel, one of said solenoids, when energized by said first electric signal causing the spare symbol to be disposed in printing position, and the other of said solenoids when energized by said first electric signal causing the strike symbol to be disposed in printing position.

14. The electrically operated printer of claim 11 wherein each of said two characters on said printing wheel extends radially beyond all of the characters on said plurality of printing wheels, whereby, when one of said two characters is disposed in printing position, the raised characters on said plurality of printing wheels which are disposed in printing position are prevented from printing by said one of said two characters of said single wheel.

References Cited by the Examiner UNITED STATES PATENTS 445,251 1/91 Massey 101-70 1,065,792 6/13 Ellis 235-6018 X 2,087,315 7/37 Bugg 346-89 2,148,861 2/39 Kall 346-94 2,281,742 5/42 Bradt 235-6018 LEO SMILOW, Primary Examiner. 

11. AN ELECTRICALLY OPERATED PRINTER WHICH AUTOMATICALLY DISPOSES IN A PRINTING POSITION IN RESPONSE TO A FIRST ELECTRIC SIGNAL A DESIRED SET OF CHARACTERS TO BE PRINTED AND THEREAFTER CAUSES SAID CHARACTERS TO PRINT ON A PRINTING SURFACE IN RESPONSE TO A SECOND ELECTRIC SIGNAL, WHICH COMPRISES: A PLURALITY OF ROTATABLE PRINTING WHEELS ROTATABLY MOUNTED ON A SUPPORT, EACH HAVING THE NUMERALS ZERO THROUGH NINE SPACED AROUND THE CIRCUMFERENCE THEREOF, EACH OF SAID WHEELS BEING ROTATABLE SO THAT ANY ONE NUMERAL ON EACH WHEEL MAY BE DISPOSED IN SAID PRINTING POSITION, SAID WHEELS FORMING A COUNTER ADAPTED TO INCREASE THE NUMERICAL VALUE OF THE NUMBER DISPOSED IN SAID PRINTING POSITION IN RESPONSE TO SAID FIRST ELECTRIC SIGNAL; A SINGLE ROTATABLE PRINTING WHEEL ROTATABLY MOUNTED ON SAID SUPPORT, SAID WHEEL HAVING TWO RAISED CHARACTERS SPACED AROUND ITS CIRCUMFERENCE AND BEING ROTATABLE SO THAT EITHER OF SAID TWO CHARACTERS MAY BE DISPOSED IN SAID PRINTING POSITION IN RESPONSE TO SAID FIRST ELECTRIC SIGNALS; MEANS FOR ROTATING SAID PLURALITY OF WHEELS, SAID MEANS INCLUDING A FIRST SOLENOID MECHANICALLY LINKED TO SAID PLURALITY OF WHEELS SO THAT SAID WHEELS ARE ROTATED TO INCREASES THE NUMERICAL VALUE OF THE NUMBER DISPOSED IN SAID PRINTING POSITION BY ONE EACH TIME SAID FIRST SOLENOID IS ENERGIZED, SAID SOLENOID BEING REPEATEDLY ENERGIZABLE BY SAID FIRST ELECTRIC SIGNAL; MEANS FOR ROTATING SAID SINGLE ROTATABLE PRINTING WHEEL IN RESPONSE TO SAID FIRST ELECTRIC SIGNAL WHICH IS ONE OF TWO ELECTRIC SIGNALS, ONE OF WHICH CAUSES ONE OF SAID TWO CHARACTERS TO BE DISPOSED IN PRINTING POSITION, AND THE OTHER OF WHICH CAUSES THE OTHER OF SAID TWO CHARACTERS TO BE DISPOSED IN PRINTING POSITION; HOLDING MEANS FOR PIVOTABLY HOLDING SAID SUPPORT AWAY FROM CONTACT WITH SAID PRINTING SURFACE; MEANS FOR PIVOTING SAID SUPPORT ON SAID HOLDING MEANS SO THAT SAID DISPOSED CHARACTERS STRIKE SAID PRINTING SURFACE, SAID MEANS INCLUDING A SECOND SOLENOID WHICH IS ENERGIZED BY SAID SECOND ELECTRIC SIGNAL; AND MEANS FOR RESTORING SAID SUPPORT TO ITS POSITION AWAY FROM CONTACT WITH SAID PRINTING SURFACE. 